question

Thanks, Cliff. You seem to have solved this problem.

Thanks, Cliff, for identifying the problem patient (ID1561). I could not figure out the solution, but I noted several quirks, and was hoping you could solve the puzzle from here. One significant issue is that, in spite of progressing through the track receiving care, the patient is assigned the label of a_LWBS. Thus, he should have left but stayed.

Oddity 1 - Patient pulls the resource physician to the waiting room for an assessment (below). An additional oddity is the fact that this physician comes from a different zone and group that the patient was assigned to.

Oddity 2 - Patient pulls more resources to the waiting room (below), as seen here receiving blood draw and X-ray

Oddity 3 - Patient is seen sneaking out of the model (below) without completing the X-ray activity.

Oddity 4 - Waiting room is reserved for patient just as a bed is reserved for a patient when transported to X-ray

Oddity 5 - In spite of the fact that the patient moves through the track receiving care, he is a LWBS patient (as seen below: a_LWBS = 1). This label was assigned at the waiting room location when he met the “Patient Condition…Patient Leaves Early” criteria.

Jim,

Your waiting room is "going into hold" because it gets reserved by a patient (ESI Level 3_ID1561) who happens to be in the waiting room for 1) a Nurse Assess between 05:22:30.00 and 05:22:39.85, and 2) an MD Assess between 05:22:39.85 and 05:22:46.46, and ultimately try to receive an X-Ray at time 05:23 which either will cause an error about an invalid staff member (because the required staff for Zap_Patient is based on patient's current location) or if a staff member is called, the patient will reserve the waiting room when he leaves it.

I assume you do not wish to have patients receive care in the waiting room, so you will want to look over your track to see why a patient is sometimes serviced in the waiting room. A good place to start would be to run Scen 2, Rep 1 up till just before patient ID1561 receives a Nurse Assess at time 05:22:30.

I've attached a screen shot of the Activity Table for patient ID 1561 in case it can give you any useful clues. Let me know if you can't figure out how it is possible for patient ID 1561 to be in the waiting room while receiving care (assuming of course that this is not what you expect), and I'll see if I can help you out.

Hi Cliff,

Thanks for pointing out my stupid mistakes with predecessors/next activity. After removing the self-inflicted bug, the new model version fixes the first error (#738). However, I am still plagued with a set of waiting room chairs that go into hold mode for no apparent reason. The following error occurs in Scenario 2, Replication 1:

Also, thanks for advising me on Lou's work in this topic. I have studied his technique, and like the method by which it processes the LWBS patient. Unfortunately, the error above was still present when I applied his method.

Thanks,

Jim

ed-ver-32b-w-lwbs-function.fsm

Jim,

I noticed you were kicking off activity 141 twice (once with a predecessor and once with a next activity). After removing the Next Activity from activity 140 in the attached model, I do not see any errors. See if it's doing what you expect now.

ed-ver-30-ck.fsm

p.s. as for LWBS modeling, you might want to make contact with @Lou Keller regarding his famous "impatience curve" approach. It uses an explicit activity for removing the patient from the model after they run out of patience for waiting. I think it is a better approach than to use the fields we provide on waiting rooms, but I'll let him try to sell you on it... ;-)

Matthew,

Did the software developers ever come up with a solution to these error messages?

Thanks,

Jim

lou.keller@flexsim

matthew.gillespie@flexsim

It looks like that question was eventually resolved in a separate private question. The main issue is that the patient may have started an activity and possible allocated staff by the time they choose to leave early. The Patient Condition Changes code was slightly modified to better handle this scenario:

First, the condition field now checks if the patient has allocated any staff. So include the int StaffAllocated line at the top and then throw the !staffAllocated && expression at the start of the condition field.

Second, the terminate activity line was added near the end of the code to stop whatever the patient's current activity is.

Here is the code used in the picture above so you can copy it:

...

/**Determine whether a patient will leave early \n*/
/**\nEarly Exit Condition: */

int PASS = true;
int staffAllocated = getobjecttype(getrequiredresource(patient,getvarnum(patient, VAR_ActivityRow),STAFF,1)) == OBJECT_Staff;
double waitingTime = time() - getentrytime(patient);
int PCI = getlabel(patient, "PCI");
int condition = /**/!staffAllocated && ( (PCI == 1 && waitingTime > uniform(120,180,1)) || (PCI == 2 && waitingTime > uniform(90,240,1)) );


if(condition == false)
	return 0;


if(condition)
{
	...
	if(!connected)
	{
		contextdragconnection(current, lwbs_obj, "A");
		openallip(lwbs_obj);
	}
	terminateactivity(patient, getvarnum(patient,VAR_ActivityRow));
	// Change the patient's current activity's type to "Patient Travels Unattended" (regardless of what activity type
	...
}
...